Johannesburg: South African Anti-apartheid icon Nelson Mandela's family on Monday visited him as his condition improved further on the fifth day in a hospital where he is being treated for a recurrence of pneumonia, the presidency said.

There are no details yet on how much longer he will stay there. "[Mr Mandela] spent part of Family Day with some members of his family, who appreciate the support they have been receiving from the public," the statement said. It did not specify how many visitors he had had or who they were.

A previous statement last evening said the 94-year-old former South African president "had a restful day" and was improving.

"Nelson Mandela had a restful day," President Jacob Zuma's office said in a statement, adding doctors treating him had reported "a further improvement in his condition".

The Government is satisfied that the doctors are providing the former President with the best medical care possible to enable his recovery and comfort, the statement said.

Zuma also thanked thousands of South Africans who prayed for Mandela at various Easter church services during the weekend.

The Nobel Peace Prize laureate, often fondly called by his clan name 'Madiba', was re-admitted to an undisclosed hospital in Pretoria before midnight on Wednesday for the third time in four months.

Earlier this month, Mandela spent a night at a Pretoria hospital where he underwent a successful medical examination.

Three months ago, he was admitted for 18 days for treatment of the lung infection and surgery to extract gallstones. It was his longest stint in hospital since his release from prison in 1990.

Mandela had a long history of lung problems, dating back to the time when he was a political prisoner on Robben Island during apartheid. While in jail he contracted tuberculosis.

Mandela served as South Africa's first black president from 1994 to 1999 and is widely regarded as the father of the nation for leading the struggle against apartheid and for democracy.